1. Field
One embodiment of the present invention relates to an encoding technique for moving images, which is suitably applicable to information processing apparatuses such as personal computers.
2. Description of the Related Art
In recent years, personal computers equipped with software encoders, which encode moving images by software, have come into widespread use. Further, recently, attention has been given to H.264/Advanced Video Coding (AVC) as a next-generation moving-image compression encoding technique. H.264/AVC is a compression encoding technique with higher efficiency than conventional compression encoding techniques such as MPEG2 and MPEG4. Therefore, encoding processing compliant with H.264/AVC requires a processing amount larger than that required in conventional compression encoding techniques such as MPEG2 and MPEG4. Thus, there have been made various propositions to reduce the encoding processing amount of moving images thereof (for example, refer to Jpn. Pat. Appln. KOKAI Pub. No. 2006-332986).
Encoding processing compliant with H.264/AVD has a large processing amount in a determination of a prediction mode for each macroblock. In particular, in High Profile (HP), when the block size of the prediction mode is 8×8 pixels or more in inter-prediction, it is possible to select the most suitable one from either of a discrete cosine transform (DCT) with a block size of 4×4 pixels and DCT with a block size of 8×8 pixels. Therefore, the processing amount required for prediction mode determination of the inter-prediction increases in proportion to the number of prediction mode candidates (since there are substantially prediction modes of a number twice as large as the number of selectable prediction modes). Thus, it is strongly desired to achieve a mechanism for efficiently performing prediction mode determination, while deterioration in image quality is suppressed.